Check for type in list

Line 179 in 5bed0c6

parameters[k] = ",".join(v)

Just because its a list, doesn't mean we can str-concat it. If a set of timestamps is passed to the time parameter this will fail with :

    response = client.post(
  File "/home/mschott/.cache/pypoetry/virtualenvs/osm-element-vectorisation-xti8G22H-py3.10/lib/python3.10/site-packages/ohsome/clients.py", line 278, in post
    self._format_parameters(params)
  File "/home/mschott/.cache/pypoetry/virtualenvs/osm-element-vectorisation-xti8G22H-py3.10/lib/python3.10/site-packages/ohsome/clients.py", line 372, in _format_parameters
    self._parameters = format_lists(self._parameters)
  File "/home/mschott/.cache/pypoetry/virtualenvs/osm-element-vectorisation-xti8G22H-py3.10/lib/python3.10/site-packages/ohsome/helper.py", line 179, in format_lists
    parameters[k] = ",".join(v)
TypeError: sequence item 0: expected str instance, numpy.datetime64 found